The present invention relates to beverage servers for retaining beverages at a desired heated temperature.
Prior art beverage servers have attempted to maintain the temperature of a brewed beverage retained therein in a variety of ways. One form of beverage server utilizes a heat resistant and heat conductive material for a beverage reservoir and places an exposed flame using a product such as gelled fuel thereunder to provide heat. One problem with this type of beverage server is that an exposed flame is presented to the customers and that the flame does not necessarily maintain a consistent or desired beverage temperature.
Another form of beverage dispenser which provides heat to a server is a warmer plate type device. The server is constructed of a material which will conduct heat from a warmer plate positioned therebelow. Heat is produced by the warmer plate, generally at a consistent power level. Typically, a glass, metal or ceramic reservoir is required in order to conduct heat to the beverage retained therein. This type of server provides heat to the beverage retained therein but also places an active heating element in a position which may be accessible to a user. Such an active heating element exposed to customers may be less than optimal.
Another way in which the prior art has attempted to maintain a brewed beverage in a heated condition and to present the beverage in a server for use by a consumer is the use of glass-insulated reservoirs and air pots. The glass insulated reservoirs provide temperature retention and may be heated by a warming device as discussed above. However, such glass reservoirs are subject to damage upon impact. As such, it would be preferable to provide a non-breakable reservoir structure for such beverage servers especially because they are presented to customers for use and such consumers may be less than careful in using such servers.
The air pots mentioned above help to slow the loss of heat from beverage servers but generally are not used with an active heat maintaining system. Air pots typically use a glass reservoir and are subject to the problems discussed hereinabove with regard to glass reservoirs. Further, the air pots use a pressurization system in order to drive coffee through a dispensing tube in the reservoir. As such, atmospheres are actively and intentionally introduced into the air pot reservoir. Generally, it is desirable to minimize the contact of atmosphere with coffee retained in a reservoir in order to improve and extend the flavor qualities of the coffee. Contact and exposure to air tend to reduce the flavor characteristics and degrade the coffee. As such, air pots actively introducing such air may tend to accelerate the flavor degradation.
As an additional matter, the prior art servers tend to quickly reduce the temperature of coffee when coffee is initially dispensed into a cool or unheated reservoir. As might be expected, heat from the coffee is conducted to the surrounding walls of the reservoir which thereby reduces the temperature of the beverage and reduces the time for retaining the beverage. While some reservoirs provide instructions to the food preparation employee to preheat a reservoir with heated water, the food preparation employees may forget or fail to preheat the reservoirs thereby creating the problems associated with cold reservoirs.
Finally, as might be expected with other foods, coffee as well as other brewed beverages have a "life" during which the flavor characteristics are optimal. Freshly brewed coffee, for example, sitting in an open pot will have a "life" of approximately 20-30 minutes. The life is extended by reducing the evaporative loss of the coffee, minimizing the atmospheric contact with the coffee, regulating the temperature conducted to the coffee to maintain the coffee at a desired serving temperature, preventing overcooking of the coffee, and maintaining the temperature at a desired temperature range. However, prior art devices tend to expose the coffee to the atmosphere, fail to regulate the temperature of the heat provided to maintain the coffee in a heated condition, and tend to "cook" the coffee such as by leaving the coffee on an unregulated warmer.
For the foregoing reasons, as well as other reasons which may not have been discussed hereinabove, there is a need for an improved beverage server which may be presented to customers for self-dispensing.